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  • SQL行列转换脚本

    --行列互转
    /*
    *****************************************************************************************************************************************************
    以学生成绩为例子,比较形象易懂
    *****************************************************************************************************************************************************
    */

    --1、行互列
    --
    > --> 生成測試數據

    IF NOT OBJECT_ID('Class') IS NULL
    DROP TABLE Class
    Go
    CREATE TABLE Class
    (
    [Student] NVARCHAR(2) ,
    [Course] NVARCHAR(2) ,
    [Score] INT
    )
    INSERT Class
    SELECT N'张三', N'语文', 78
    UNION ALL
    SELECT N'张三', N'数学', 87
    UNION ALL
    SELECT N'张三', N'英语', 82
    UNION ALL
    SELECT N'张三', N'物理', 90
    UNION ALL
    SELECT N'李四', N'语文', 65
    UNION ALL
    SELECT N'李四', N'数学', 77
    UNION ALL
    SELECT N'李四', N'英语', 65
    UNION ALL
    SELECT N'李四', N'物理', 85
    Go
    --2000方法:
    动态:

    DECLARE @s NVARCHAR(4000)
    SET @s = ''
    SELECT @s = @s + ',' + QUOTENAME([Course]) + '=sum(case when [Course]='
    + QUOTENAME([Course], '''') + ' then [Score] else 0 end)'
    FROM Class
    GROUP BY [Course]
    EXEC('select [Student]'+@s+' from Class group by [Student]')


    生成静态:

    SELECT [Student], [数学] = SUM(CASE WHEN [Course] = '数学' THEN [Score]
    ELSE 0
    END),
    [物理] = SUM(CASE WHEN [Course] = '物理' THEN [Score]
    ELSE 0
    END), [英语] = SUM(CASE WHEN [Course] = '英语' THEN [Score]
    ELSE 0
    END),
    [语文] = SUM(CASE WHEN [Course] = '语文' THEN [Score]
    ELSE 0
    END)
    FROM Class
    GROUP BY [Student]

    GO
    动态:

    DECLARE @s NVARCHAR(4000)
    SELECT @s = ISNULL(@s + ',', '') + QUOTENAME([Course])
    FROM Class
    GROUP BY [Course]
    EXEC('select * from Class pivot (max([Score]) for [Course] in('+@s+'))b')

    生成静态:
    SELECT *
    FROM Class PIVOT
    ( SUM([Score]) FOR [Course] IN ( [数学], [物理], [英语], [语文] ) ) b

    生成格式:
    /*
    Student 数学 物理 英语 语文
    ------- ----------- ----------- ----------- -----------
    李四 77 85 65 65
    张三 87 90 82 78

    (2 行受影响)
    */

    ------------------------------------------------------------------------------------------
    go
    --加上总成绩(学科平均分)

    --2000方法:
    动态:

    DECLARE @s NVARCHAR(4000)
    SET @s = ''
    SELECT @s = @s + ',' + QUOTENAME([Course]) + '=sum(case when [Course]='
    + QUOTENAME([Course], '''') + ' then [Score] else 0 end)'
    FROM Class
    GROUP BY [Course]
    EXEC('select [Student]'+@s+',[总成绩]=sum([Score]) from Class group by [Student]')
    --加多一列(学科平均分用avg([Score]))

    生成动态:

    SELECT [Student], [数学] = SUM(CASE WHEN [Course] = '数学' THEN [Score]
    ELSE 0
    END),
    [物理] = SUM(CASE WHEN [Course] = '物理' THEN [Score]
    ELSE 0
    END), [英语] = SUM(CASE WHEN [Course] = '英语' THEN [Score]
    ELSE 0
    END),
    [语文] = SUM(CASE WHEN [Course] = '语文' THEN [Score]
    ELSE 0
    END), [总成绩] = SUM([Score]) --加多一列(学科平均分用avg([Score]))
    FROM Class
    GROUP BY [Student]

    go

    --2005方法:

    动态:

    DECLARE @s NVARCHAR(4000)
    SELECT @s = ISNULL(@s + ',', '') + QUOTENAME([Course])
    FROM Class
    GROUP BY [Course]
    --isnull(@s+',','') 去掉字符串@s中第一个逗号
    EXEC('select [Student],'+@s+',[总成绩] from (select *,[总成绩]=sum([Score])over(partition by [Student]) from Class) a
    pivot (sum([Score]) for [Course] in(
    '+@s+'))b ')

    生成静态:

    SELECT [Student], [数学], [物理], [英语], [语文], [总成绩]
    FROM ( SELECT * ,
    [总成绩] = SUM([Score]) OVER ( PARTITION BY [Student] )
    FROM Class
    ) a --平均分时用avg([Score])
    PIVOT
    ( MAX([Score]) FOR [Course] IN ( [数学], [物理], [英语], [语文] ) ) b

    生成格式:

    /*
    Student 数学 物理 英语 语文 总成绩
    ------- ----------- ----------- ----------- ----------- -----------
    李四 77 85 65 65 292
    张三 87 90 82 78 337

    (2 行受影响)
    */

    go

    --2、列转行
    --
    > --> (Roy)生成測試數據

    IF NOT OBJECT_ID('Class') IS NULL
    DROP TABLE Class
    Go
    CREATE TABLE Class
    (
    [Student] NVARCHAR(2) ,
    [数学] INT ,
    [物理] INT ,
    [英语] INT ,
    [语文] INT
    )
    INSERT Class
    SELECT N'李四', 77, 85, 65, 65
    UNION ALL
    SELECT N'张三', 87, 90, 82, 78
    Go

    --2000:

    动态:

    DECLARE @s NVARCHAR(4000)
    SELECT @s = ISNULL(@s + ' union all ', '') + 'select [Student],[Course]='
    + QUOTENAME(Name, '''')--isnull(@s+' union all ','') 去掉字符串@s中第一个union all
    + ',[Score]=' + QUOTENAME(Name) + ' from Class'
    FROM syscolumns
    WHERE ID = OBJECT_ID('Class')
    AND Name NOT IN ( 'Student' ) --排除不转换的列
    ORDER BY Colid
    EXEC('select * from ('+@s+')t order by [Student],[Course]')
    --增加一个排序

    生成静态:
    SELECT *
    FROM ( SELECT [Student], [Course] = '数学', [Score] = [数学]
    FROM Class
    UNION ALL
    SELECT [Student], [Course] = '物理', [Score] = [物理]
    FROM Class
    UNION ALL
    SELECT [Student], [Course] = '英语', [Score] = [英语]
    FROM Class
    UNION ALL
    SELECT [Student], [Course] = '语文', [Score] = [语文]
    FROM Class
    ) t
    ORDER BY [Student], [Course]

    go
    --2005:

    动态:

    DECLARE @s NVARCHAR(4000)
    SELECT @s = ISNULL(@s + ',', '') + QUOTENAME(Name)
    FROM syscolumns
    WHERE ID = OBJECT_ID('Class')
    AND Name NOT IN ( 'Student' )
    ORDER BY Colid
    EXEC('select Student,[Course],[Score] from Class unpivot ([Score] for [Course] in('+@s+'))b')

    go
    SELECT Student, [Course], [Score]
    FROM Class UNPIVOT
    ( [Score] FOR [Course] IN ( [数学], [物理], [英语], [语文] ) ) b

    生成格式:
    /*
    Student Course Score
    ------- ------- -----------
    李四 数学 77
    李四 物理 85
    李四 英语 65
    李四 语文 65
    张三 数学 87
    张三 物理 90
    张三 英语 82
    张三 语文 78

    (8 行受影响)
    */
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  • 原文地址:https://www.cnblogs.com/ToddLai/p/2287365.html
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